1. Field of Invention
The present invention relates to a structural design of a protective cover for a heat-conductive medium, and more particularly to a protective cover for a heat-conductive medium suitable for a heat sink apparatus.
2. Related Art
Electronic elements in the computer apparatus, such as central processing unit (CPU) chips and power integrated circuits (ICs), etc., generate heat when carrying out operations. The watt consumption of CPU chips has become higher and higher, and the high integrity of ICs also centralizes the heat source, such that not only does intense heat occur during the operation, but the resulting heat increases as the operation speed increases. Since the operation temperature has severe impact on whether the computer apparatus will crash or not, appropriate temperature control will provide the computer apparatus with high reliability and allow the heat-emitting electronic elements to operate stably.
In order to reduce the working temperature of the heat-emitting electronic elements while maintaining effective operation, various heat sink apparatuses are designed through the heat sinking design. The heat resistance of the surface can be reduced by closely contacting the heat sink apparatus with the heat-emitting electronic element, and the heat-conductive effect between the heat sink apparatus and the heat-emitting electronic element can be enhanced by coating a heat-conductive medium there-between.
As for manufacturers of heat sink apparatuses, a heat-conductive medium is generally arranged on a heat sink apparatus in advance, to facilitate shipment for the customer. However, during the transportation of heat sink apparatuses, it is rather easy for the heat-conductive medium to pollute the ambience, or to be scraped and squeezed by the surrounding objects. Thus, the heat-conductive medium must be sufficiently protected while transporting heat sink apparatuses.
U.S. Pat. No. 5,897,917 discloses a method for applying a protective membrane directly onto the bottom surface of a heat sink apparatus provided with a heat-conductive medium, to protect the heat-conductive medium. Although this method can prevent the heat-conductive medium from being polluted by the ambience and vice versa, the protective membrane directly contacted with the heat-conductive medium is likely to be squeezed to be deformed or scraped by ambient external forces during the transportation of the heat sink apparatus.
U.S. Pat. No. 6,049,458 discloses a protective cover body for a heat-conductive medium, wherein the central part of the cover body corresponds to a heat sink apparatus with a heat-conductive medium, while the edge of the cover body is adhered and secured to the bottom surface of the heat sink apparatus. Although deforming and scraping of the heat-conductive medium due to squeezing can be reduced in this way, an adhesive object tends to be attached on the surface of the heat sink apparatus when the cover body is torn off, resulting in a non-uniform surface of the heat sink apparatus, and work for clearing the adhesive object is required, such that the heat sink effect is greatly reduced. In addition, a poor adhesion occurs when the protective cover body is stuck onto the surface of the heat sink apparatus, thereby the protective cover body is unable to be firmly anchored and tends to fall off there-from, being unable to protect the heat-conductive medium.